1. Field of the Invention
The present invention relates to wall construction, and more particularly to a new and improved means for bracing parallel studs, draft dampening between parallel studs within interior wall structures, and anchoring hand rails and grab bars to walls using a single unitary device. The present invention provides the largest percentage of closure between metal studs thereby forming a fire stop (also known as a draft dampener) within the completed wall assembly thereby preventing fire from traveling between parallel studs within a completed wall assembly. Simultaneously, the present invention provides a means to reinforce construction studs by transversely bracing the parallel studs against each other. Additionally, the claimed invention provides a means for anchoring wall mounted structures, e.g., handrails and grab bars.
2. Description of Prior Art
Historically, the framework of a building wall was formed entirely of wood members, including wooden studs. In recent years, however, the use of metal studs has gained acceptance, and is mandated for use in buildings greater than four stories, i.e., commercial buildings, such as office buildings and hospitals. It has been found that metal studs can be advantageously employed, since a suitable metal, such as galvanized steel, is stronger than wood, will not rot, is not subject to damage by pests such as termites, remains resistant to fire, and is economically feasible.
Metal studs are typically formed of sheet metal bent to encompass a cross sectional area having nominal dimensions of two inches by four inches. To conform to architectural plans and building code requirements, metal studs are formed of sheet metal bent into generally "u"-shaped cross-section in which a relatively broad central base is flanked by a pair of narrower sides that are bent at right angles to the base. The base typically has a uniform nominal width of either four inches or 35/8 inches which is commonly referred to as the "web." The sides of the "u"-shaped stud typically extends a nominal distance of two inches from the base which are commonly referred to as "flanges." To enhance structural rigidity the flanges of the stud, the flanges are normally bend over into a plane parallel to and spaced from the plane of the web. These turned over edges of the sides thereby form marginal lips which are typically one quarter to one half inch in width. Conventionally, the metal studs are erected with the webs oriented on the same side in the same direction.
In building construction there are certain situations which require the building studs to be braced or linked transversely to provide enhanced structural rigidity. The studs must be transversely bridged when they are over eight feet in length so that they provide adequate stability in a lateral direction within the wall which they support.
In certain instances, the metal studs require transverse backing between the studs in a building so to provide structural support against forces acting normal to or parallel to the plane of the wall assembly. For example, structural backing must be provided between adjacent parallel studs to provide necessary structural stability for the installation wall structures such as hand rails and grab bars must which conform to requirements of the Americans with Disabilities Act, i.e., withstand 250 pounds of point load pressure outward and downward parallel to the plane of the wall.
The use of fire-stops, bridging and backing in construction trade is well known in the prior art. Construction Codes and Fire Codes requires that these devices be positioned between metal studs to: (1) reinforce uniformly laterally spaced parallel metal studs; (2) discourage the spread of fire, smoke and gases within interior walls; and (3) anchor hand rails and grab bars to metal studs. The claimed invention is an improvement over the prior art based upon the accomplishment of these three tasks using only one unitary device in lieu of two or more separate devices as required by the prior art. It is therefore an object of the present invention to provide a new and improved unitary bridging, backing and fire-stop device which has all the advantages of the prior and none of the disadvantages.
First, the claimed invention provides for bridging between parallel metal studs to reinforce the studs. The device bridges the span between the parallel studs thereby reinforcing studs one against the other.
Second, the claimed invention provides for fire stopping in accordance with the BOCA National Building Code and the anticipated International Building Code. The BOCA Code defines "draft stopping" as "building materials installed to prevent the movement of air, smoke, gases, and flame to other areas of the building through large concealed passages." See BOCA .sctn.7.02.0 (1999). The International Building Code ("I.B.C.") defines a "Fireblocking"as "building materials installed to resist the free passage of flame to other areas of the building through concealed spaces." International Building Code .sctn.702.1 (1998). The I.B.C. further defines a "Draft Stop" as "a material, device or construction installed to restrict the movement of air within open spaces of concealed areas of building components . . . " Id. The claimed unitary solid metal invention installed between parallel studs in interior wall assemblies creates a fire-resistive blockage within the wall assembly which impedes the movement of air, smoke, gases and flames within the hollow interior wall assembly by sectioning the hollow cavity formed within interior wall assemblies. The use of the claimed invention conforms to the requirements of the above building codes.
Third, the claimed invention serves as backing for the installation of handrails and grab bars which are now required by the Americans with Disabilities Act. The claimed invention anchors the hand rail and grab bar to the parallel studs which form the interior wall assemblies. The anchorage to the parallel studs provided by the claimed invention permits the installation of handrails and grab bars which can with stand 250 pounds of point load pressure in accordance with the Americans with Disabilities Act. See Americans With Disabilities Act (ADA) Accessibility Guidelines for Buildings and Facilities, 56 Federal Register 35408 (Jul. 26, 1991).
Another object of the claimed invention is the provision of a unitary device for fire stop, bridging and backing which is simple in construction and economical in cost. Prior to the existence of the claimed invention, contractors were required to install at least two separate devices to achieve the three objects of the claimed invention: (1) metal stud support (i.e., bridging); (2) fire stoppage (vis a vis draft dampening); and, (3) a means for anchoring hand rails and grab bars. Accordingly, the cost of construction is now reduced since only the claimed invention may be used in lieu of two separate devices to accomplish bridging, fire stop and backing.
Still another object of the claimed invention is that it may be used in wall assemblies formed by vertical parallel studs or horizontal parallel studs.
One such product which may be replaced by the claimed invention is protected by U.S. Pat. No. 4,791,766 issued on Dec. 20, 1988. The product claimed by U.S. Pat. No. 4,791,766 merely provides a fire stop within interior wall assemblies without providing for support of parallel studs and a means to anchor hand rails and grab bars.
Similarly, U.S. Pat. No. 4,658,556 issued on Apr. 21, 1987 merely discloses a device for the support of parallel studs. The invention claimed in U.S. Pat. No. 4,658,556 is devoid of fire blocking capabilities as well as suitable means to secure hand rails and grab bars. In comparison, the invention claimed herein is easier and cheaper to install in light of the use of self-tapping screws in lieu of metal pegs impacted using a clincher device which require additional labor and steel costs.
Prior art claimed by U.S. Pat. No. 5,189,857 merely provided bridging to support parallel studs and backing to anchor hand rails and grab bars. However, to serve as an anchor for handrails and grab bars, the invention claimed in U.S. Pat. No. 5,189,857 is installed in a manner which compromises its ability to serve as a fire stop. Likewise, if the claimed invention was installed horizontally to serve as a fire stop mechanism the invention could not simultaneously be used to anchor hand rails and grab bars.
Likewise, U.S. Pat. No. 1,867,449 issued on Jul. 12, 1932 merely provides bridging to support parallel studs and fire block capabilities. The invention fails to provide a means for the attachment of hand rails and grab bars. Similarly U.S. Pat. Nos. 1,867,449, 2,994,114, and Des. 271,849 suffer from the same deficiency as U.S. Pat. No. 1,867,449.
Additional prior art known as NOTCH-TITE.RTM. and STAIR-TITE.TM. manufactured by Metal-Lite, Inc., Anaheim, Calif. does not possess the ability to provide bridging, backing and fire stop in one unitary device. NOTCH-TITE.RTM. and STAIR-TITE.TM. alone serve only as a backing device for hand rails and grab bars. Specifically, NOTCH-TITE.RTM. is installed transversely across studs in a wall assembly that form level corridors for the purpose of attaching hand rails and grab bars. In contrast, STAIR-TITE.TM. is installed perpendicularly across studs which form a wall assembly in stair wells for the purpose of attaching hand rails and grab bars in coordination with the rise of the stairs. Both NOTCH-TITE.RTM. and STAIR-TITE.TM. fail to provide bridging support between parallel studs because the support is not centrally located between the studs, but rather is attached along one side of the parallel studs without reinforcing the opposite side. In the absence of central support between the parallel studs, the parallel studs will twist and potentially buckle on the unsupported side. Additionally, both NOTCH-TITE.RTM. and STAIR-TITE.TM. fail to provide any means for fire stop. Accordingly, a separate fire stop device and bridging device must be employed to obtain the results of the claimed invention. The installation of these two additional devices in combination with NOTCH-TITE.RTM. or STAIR-TITE.TM. increases construction costs due to the requirement of additional materials and increased installation time.
"Black Iron" is another form of bridging which pre-dates the claimed invention. "Black Iron" comprises a metal "u"-shaped channel which is run through the parallel apertures of the parallel studs to reinforce the parallel studs. "Black Iron" fails to incorporate any means for fire stop or backing for hand rails or grab bars. Accordingly, a separate fire stop device and backing device must be employed to obtain the results of the claimed invention. The installation of these two additional devices in combination with "Black Iron" increases construction costs due to the requirement of additional materials and increased installation time.